Retinal malfunction is a leading cause of blindness and visual impairment. Implantation of a retinal prosthesis in the eye may be helpful in restoring some vision to individuals suffering from blindness of retinal origin. A variety of retinal prostheses have been described in the patent literature.
U.S. Pat. No. 8,150,526 to Gross, which is incorporated herein by reference, describes apparatus including an external device, including a mount, which is placed in front of an eye of a subject. A laser is coupled to the mount and configured to emit toward the eye radiation that is outside of 380-750 nm. A partially-transparent mirror is coupled to the mount. An intraocular device is implanted entirely in the subject's eye, and includes a plurality of stimulating electrodes, and an energy receiver, which receives the radiation from the laser and generates a voltage drop in response thereto. A plurality of photosensors detect photons and generate a signal in response thereto. Driving circuitry is coupled to the energy receiver and to the photosensors, and receives the signals from the photosensors and utilizes the voltage drop to drive the electrodes to apply currents to the retina in response to the signals from the photosensors. Other embodiments are also described.
U.S. Pat. No. 8,428,740 to Gefen, which is incorporated herein by reference, describes apparatus including an external device including a mount, which is placed in front of an eye of a subject. A power source is coupled to the mount and emits energy toward the eye. An intraocular device is implanted entirely in the subject's eye, and includes a control unit, a plurality of stimulating electrodes, and an energy receiver, which receives the energy from the power source and generates a voltage drop in response. A plurality of photosensors detect photons and generate a signal in response. Driving circuitry is coupled to the energy receiver and to the photosensors, and drives the electrodes to apply electrical charges to a retina in response to the signals from the photosensors. The external device modulates the emitted energy, and the control unit demodulates the modulated energy to regulate an operation parameter of the intraocular device. Other embodiments are also described.
U.S. Pat. No. 8,442,641 to Gross, which is incorporated herein by reference, describes apparatus for use with an external non-visible light source. The apparatus comprises an intraocular device configured for implantation in a human eye, and comprising an energy receiver. The energy receiver is configured to receive light emitted from the external non-visible light source, and extract energy from the emitted light for powering the intraocular device. The intraocular device is configured to regulate a parameter of operation of the intraocular device based on a modulation of the light emitted by the external non-visible light source and received by the energy receiver. Other embodiments are also described.
US Patent Application 2011/0172736 to Gefen, which is incorporated herein by reference, describes apparatus configured for implantation in a body of a subject. The apparatus includes a support substrate, and at least 500 electrodes protruding at least 50 um from the support substrate, each electrode having (a) a distal tip, (b) an electrically-exposed tip portion, and (c) a cross-section of 50-1500 um2, 20 um from the distal tip. Other embodiments are also described.
US Patent Application 2012/0041514 to Gross, which is incorporated herein by reference, describes an external device including a mount, which is placed in front of a subject's eye. A laser is coupled to the mount and emits radiation that is outside of 380-750 nm. A partially-transparent mirror is coupled to the mount. An intraocular device is implanted entirely in the subject's eye, and includes a plurality of stimulating electrodes, and an energy receiver, which receives the radiation from the laser and generates a voltage drop. A plurality of photosensors detect photons and generate a signal. Driving circuitry is coupled to the energy receiver and to the photosensors, and receives the signals from the photosensors and utilizes the voltage drop to drive the electrodes to apply currents to the retina in response to the signals from the photosensors. Other embodiments are also described.
US Patent Application 2012/0221103 to Liran, which is incorporated herein by reference, describes a medical device including an array of electrodes, configured for implantation in contact with tissue in an eye of a living subject. Driver circuitry is configured to drive the electrodes in an alternating pattern, such that different groups of the electrodes are driven to stimulate the tissue during different, predetermined respective time periods. A power sensor may be coupled to deactivate a first group of the electrodes when the available electrical power drops below a predetermined threshold, while a second group of the electrodes remains active. Other embodiments are also described.
US Patent Application 2012/0259410 to Gefen, which is incorporated herein by reference, describes apparatus for use with an external non-visible light source. The apparatus comprises an intraocular device configured for implantation in a human eye, and comprising an energy receiver. The energy receiver is configured to receive light emitted from the external non-visible light source, and extract energy from the emitted light for powering the intraocular device. The intraocular device is configured to regulate a parameter of operation of the intraocular device based on a modulation of the light emitted by the external non-visible light source and received by the energy receiver. Other embodiments are also described.